Vegetable Frittata

Name: Vegetable Frittata
Ingredients: 10 large eggs; 1/3 cup whole milk or half-and-half; Kosher salt and freshly ground black pepper, (to taste); 1 cup shredded mozzarella cheese or Gruyere cheese; 1 tablespoon olive oil; 1/2 yellow onion, (chopped); 2 cups sliced cremini mushrooms; 1 red bell pepper, (stemmed, seeds removed, and chopped); 1 small zucchini, (chopped); 2 cups fresh spinach leaves; 2 cloves garlic, (minced); 1/2 cup halved grape tomatoes; 1/4 cup freshly grated Parmesan cheese; 2 tablespoons freshly chopped basil